Ch.10

Origin: Maxilla and mandible
Insertion: into muscle and skin at angles of mouth
Action: closes lips

Orbicularis Oris

Origin: zygomatic bone
Insertion: skin and muscle at corner of mouth
Action: raises corners of mouth

Zygomaticus

Origin: mandible below incisors
Insertion: Skin of chin
Action: wrinkles chin, protrudes lower lip (as in a pout)

Mentalis

Origin: fascia of chest
Insertion: lower margin of mandible
Action: Tenses skin of neck, pulls lower lip back and down (downward sag of mouth)

Platysma

origin: arch of frontal bone above nasal bone
insertion: skin of eyebrow
action: pulls eyebrows medially and inferiorly, wrinkles skin of forhead

Corrugator supercilii

Origin: Frontal and maxillary bones
Insertion: Tissue of eyelids
Action: Closes eye, pulls eyebrow inferiorly

Orbicularis Oculi

Two part muscle consisting of the frontal and occipital bellies connected by epicranial aponeurosis. The alternate actions pulls scalp forward and backward

Epicranius (Occipitofrontalis)

Origin: epicranial aponeurosis
Insertion: skin of eyebrows and root of nose
Action: raises eyebrows and wrinkles forhead skin horizontally

Frontal belly

Origin: occipital bone and temporal bones
Insertion: epicranial aponeurosis
Action: Pulls scalp posteriorly

Occipital Belly

Origin: fascia associated with masseter muscle
Insertion: skin at angle of mouth
Action: pulls corner of lip laterally, tenses lip; synergist of zygomatic

Risorius

Origin: Zygomatic arch and bone
Insertion: angle and ramus of mandible
Action: Prime mover of jaw; closure

Masseter (1/3 chewing muscles)

Origin: Molar region of maxilla and mandible
Insertion: corner of the mouth (orbicularis oris)
Action: compress cheeks

Buccinator

Origin: temporal fossa
Insertion: coronoid process of mandible
action: closes jaw

Temporalis (1/3 chewing muscles)

Origin: Pterygoid plate of sphenoid bone
Insertion: Medial surface of mandible near the angle
Action: Acts with the lateral pterygoid muscle to protract (pull anteriorly) the mandible and promote side-to-side grinding movement

Medial Pterygoid (1/3 chewing muscles)

Origin: greater wing and lateral pterygoid plate of sphenoid bone
Insertion: Condylar process of mandible
Action: Provides side-to-side grinding movements

Lateral Pterygoid (1/3 chewing muscles)

Origin: transverse process of C1-C4
Insertion: Medial border of scapula, superior to spine
Action: elevates and adducts scapula

Levator Scapulae

Origin: Manubrium of sternum
Insertion: mastoid process of temporal bone
Action: Flexes and laterally rotates the head

Sternocleidomastoid

Origin: transverse processes of cervical vertebrae
Insertion: anterolaterally on first two ribs
Action: Elevate first two ribs

Scalenes

Origin: inferior border of rib above
Insertion: superior border of rib below
Action: Pull ribs toward one another to elevate rib cage

external intercostals

Origin: Superior border of rib below
Insertion: Inferior border of rib above
Action: Pull ribs together and depress rib

internal intercostals

Origin: Inferior, internal surface of rib cage and sternum, costal cartilages
Insertion: Central tendon
Action: Prime mover of inspiration; flattens on contraction

Diaphragm

Origin: pubic crest and symphysis
Insertion: xiphoid process and costal cartilages of ribs 5-7
Action: flexes and rotates lumbar region of vertebral column

Rectus Abdominis

Origin: fleshy strips from outer surfaces of lower eight ribs
Insertion: fibers insert into linea alba via a broad aponeurosis; some insert into pubic crest
Action: flex vertebral column and compress abdominal wall and trunk rotation and lateral flexion

External Oblique

Origin: lumbar fascia, iliac crest, inguinal ligament
Insertion: linea alba
Action: as for external oblique

Internal Oblique

Origin: inguinal ligament, lumbar fascia
Insertion: linea alba, pubic crest
Action: compresses abdominal contents

Transversus Abdominis

Origin: ribs 3-5
insertion: coracoid process of scapula
Action: with ribs fixed, pulls scapula forward and downward

Pectoralis Minor

origin: ribs 1-8
insertion: entire anterior surface of medial border of scapula
Action: Rotates scapula so its inferior angle moves laterally and upward

Serratus Anterior

Origin: ligamentum nuchae
Insertion: continuous insertion along acromion and spin of scapula
Action: Retracts, and rotates scapula

Trapezius

Origin: spinous processes of C7-T1 (minor), spinous processes of T2-T5 (major)
Insertion: medial border of scapula
Action: stabilize scapula

Rhomboid Major and Minor

Origin: Sternal End of Clavicle
Insertion: Fibers converge to insert by a short tendon
Action: Adducts medially rotates arm

pectoralis major

Origin: Lateral third of clavicle
Insertion: Deltoid tuberosity of humerus
Action: Prime mover of the arm when all its fibers contract simultaneously

Deltoid

Origin: indirect attachment via lumbodorsal fascia into spines
Insertion: Spirals around teres major
Action: Prime mover of arm extention; powerful arm addcutor; medially rotates arm

Latissimus Dorsi

Origin: subscapular fossa
Insertion: lesser tubercle of humerus
Action: Rotates arm medially

Subscapularis

Origin: supraspinous fossa of scpula
Insertion: superior part of greater tubercle of humerus
Action: Intiates abduction of arm

Supraspinatus

Origin: Infraspinous fossa of scapula
Insertion: Greater tubercle of humerus posterior to insertion
Action: Rotates arm laterally

Infraspinatus

Origin: Lateral border of dorsal scapular surface
Insertion: Greater tubercle of humerus inferior to infraspinatus insertion
Action: Same as infraspinatus

Teres Minor

Origin: Posterior surface of scapula
Insertion: Crest of lesser tubercle
Action: Extends, medially rotates, and adducts arm

Teres Major

Origin: coracoid process of scapula
Insertion: medial surface of humerus shaft
Action: Flexes and adducts arm

Coracobrachialis

Origin: Long head infraglenoid tubercle
Insertion: common tendon into olecranon on ulna
Action: Powerful forearm extensor

Triceps Brachii

Origin: Short head: coracoid
Insertion: common tendon into radial tuberosity
Action: Flexes and supinates forearm

Biceps Brachii

Origin: Anterior side of humerus
Insertion: Tuberosity and coronoid process
Action: Flexes forearm

Brachialis

Origin: Lateral supracondylar ridge at distal end of humerus
Insertion: Base of radial styloid process
Action: Synergist in flexing forearm

Brachioradialis

Origin: Medial epicondyle
Insertion: common tendon into lateral radius
Action: Pronates forearm

pronator teres

Origin: Medial epicondyle of humerus
Insertion: Base of second and third metacarpals
Action: Powerful Flexor of hand

flexor carpi radialis

Origin: Medial epicondyle
Insertion: Fascia of palm
Action: Tenses skin and fascia of palm during movements

Palmaris Longus

Origin: Medial epicondyle of humerus
Insertion: Pisiform and hamate bones
Action: Powerful flexor and adductor of hand

Flexor Carpi Ulnaris

Origin: Medial epicondyle of humerus
Insertion: four tendons into middle phalanges
Action: Flexes hand and middle phalanges of second to fifth fingers

flexor digitorum superficialis

Origin: coronoid process
Insertion: four tendons into distal phalanges
Action: Flexes distal interphalangeal joints

flexor digitorum profundus

Origin: lateral supracondylar ridge of humerus
Insertion: Base of second metacarpal
Action: Extends hand and abducts hand

Extensor Carpi Radialis Lonhgus

Origin: Lateral epicondyle of humerus
Insertion: Base of third metacarpal
Action: Extends and abducts hand

Extensor Carpi Radialis Brevis

Origin: Lateral epicondyle of humerus
Insertion: Four tendons into extensor expansions
Action: Prime mover of finger extention

Extensor Digitorum

Origin: Lateral epicondyle of humerus
Insertion: Base of fifth metacarpal
Action: Extends hand, abducts hand

Extensor Carpi Ulnaris

Origin: Lateral epicondyle of humerus
Insertion: Proximal end of radius
Action: assists biceps brachii to forcibly supinate forearm

Supinator

Origin: posterior surface of radius and ulna
Insertion: Base of first metacarpal and trapezium
Action: Abducts and extends thumb

Abductor Pollicis Longus

Origin: Dorsal shaft of radius
Insertion: Base of proximal and distal phalanx of thumb
Action: Extends thumb

extensor pollicis brevis and longus

made up of the iliacus and psoas major

Illiopsoas

Origin: iliac fossa
Insertion: Lesser trochanter of femur
Action: Prime mover for flexing thigh

Iliacus

Origin: Fleshy slips from transverse process
Insertion: Lesser trochanter of femur
Action: prime mover of thigh and flexes vertebral column laterally

Psoas Major

Origin: Anterior superior iliac spine
Insertion: medial proximal tibia
Action: Flexes, abducts and laterally rotates thigh

Sartorius

Origin: pubis
Insertion: lesser trochanter inferior to linea aspera
Action: Adducts, flexes and medially rotates thigh

Pectineus

Origin: Pubis near pubic symphysis
Insertion: linea aspera
Action: Adducts, flexes and medially rotates thigh

adductor longus

Origin: ischial and pubic rami
Insertion: linea aspera and adductor
Action: adducts and medially rotates and flexes thigh

Adductor Magnus

Origin: inferior ramus and body of pubis
Insertion: medial surface of tibia
Action: adducts thigh, flexes and medially rotates leg

Gracillis

Origin: anterior inferior iliac spine and acetabulum
Insertion: patella and tibial tuberosity
Action: Extends leg and flexes thigh at hip

Rectus Femoris

Origin: Greater Trochanter, intertrochanteric line, gluteal tuberosity, linea aspera
Insertion: Patella, Tibial tuberosity, lateral+medial condyles
Action: Extends leg and stabilizes knee

Vastus Lateralis

Origin: Intertrochanteric line, linea aspera, medial supracondylar line
Insertion: Patella, Tibial tuberosity, lateral+medial condyles
Action: Extends legs

Vastus medialis

Origin: Anterior and lateral surfaces of femur
Insertion: Patella, Tibial tuberosity, lateral+medial condyles
Action: Extends leg

vastus intermedius

Origin: Anterior aspect of iliac crest
Insertion: iliotibial tract
Action: Steadies the leg and trunk on thigh by tightening iliotibial tract

Tensor Fascia Lata

Origin: Dorsal ilium, sacrum and coccyx
Insertion: gluteal tuberosity
Action: Major extensor of thigh

Gluteus Maximus

Origin: Between anterior and posterior gluteal lines
Insertion: Short tendon into lateral aspect
Action: Abducts and medially rotates thigh

Gluteus Medius

Origin: Anterolateral surface
Insertion: superior border of greater trochanter
Action: Rotates extended thigh laterally

Piriformis

Origin: Ischial tuberosity
Insertion: head of fibula and lateral condyle of tibia
Action: Extends thigh and flexes leg

Biceps femoris

Origin: Ischial tuberosity
Insertion: Medial aspect of upper tibial shaft
Action: Extends thigh and flexes leg

Semitendinosus

Origin: ischial tuberosity
Insertion: Medial condyle of tibia
Action: Extends thigh and flexes leg

Semimembranosus

Origin: Lateral condyle
Insertion: medial cuneiform and first metatarsal
Action: Prime mover of dorsiflexion

tibialis anterior

Origin: Lateral condyle of tibia
Insertion: Middle and distal phalanges
Action: Prime mover of toe extension

extensor digitorum longus

Origin: Anteromedial fibula
Insertion: distal phalanx of great toe
Action: Extends great toe

Extensor Hallucis Longus

Origin: head and upper portion
Insertion: first metatarsal and medial cuneiform
Action: plantar flexes and everts foot

Fibularis longus

Origin: Distal fibula shaft
Insertion: lateral malleolus
Action: Plantar flexes everts foot

fibularis brevis

Origin: medial and lateral condyles of femur
Insertion: Posterior clacaneus
Action: plantar flexes foot

Gastrocnemius

Origin: Extensive origin from superior tibia
Insertion: gastrocnemius
Action: plantar flexes foot

Soleus

Origin: lateral condyle of femur
Insertion: proximal tibia
Action: Flexes, rotates leg medially to unlock extended knee when flexion begins

Popliteus

Origin: superior tibia and fibula
Insertion: medial malleolus and under arch of foot
Action: Prime mover of foot inversion

Tibialis Posterior

Origin: Posterior tibia
Insertion: medial malleolus and distal phalanges of second-fifth toes
Action: plantar flexes and inverts foot

Flexor Digitorum Longus

Origin: Midshaft of fibula
Insertion: distal phalanx
Action: plantar flexes and inverts foot; flexes great toe

Flexor Hallucis Longus